The present invention relates to a new and improved construction of a self-sucking pump apparatus for liquids, which pump apparatus is of the type comprising, a pump, a suction device and a closable pressure container or vessel.
In process technological chemical plants or installations as well as in plants or installations exploiting nuclear engineering or technology there are employed pump apparatuses. For reasons of safety or for reasons of protecting the operating personnel or workers these pump apparatuses are only partially accessible or, in fact, not at all directly accessible. Moreover, for reasons of protecting the environment, but also because of the need to protect the conveyed liquids against external influences, extremely high requirements are placed upon these pump apparatuses as concerns operational reliability and the avoidance of leakage of the pumped liquids or fluid media.
Pump apparatuses are required particularly in process technological installations in hot cells of installations working with nuclear technology, for instance, for chemical, mechanical and thermal processes and fuel preparation. Such pump apparatuses ar also utilized in process technological installations or plants which operate with high grade or highly sensitive liquids or with dangerous, especially toxic, radioactive, explosive or easily combustible liquids. The maintenance and servicing of such pump apparatuses inclusive of the assembly and disassembly thereof during repair work, without endangering the operating personnel or workers, is possible, also through the use of remotely controlled manipulator expedients or robots. Such pump apparatuses, for the aforementioned purposes, also must be capable of being rapidly and simply disassembled or dismantled and in order to accomplish the maintenance and repair work or other work which is to be carried out must be capable of being removed out of the danger zone. During such manipulation of the pump apparatuses there must be avoided the uncontrolled loss of the conveyed liquid and this is something which cannot be tolerated in such installations.
The handling in conjunction with the maintenance or servicing of the pump apparatuses which are employed within hot cells of nuclear technology is of particular importance. Upon malfunction of a pump device it is necessary under certain circumstances to shut down the entire installation or plant and then there must be accomplished numerous and complicated decontamination operations. In those situations in which the environment or surroundings of the pump apparatus cannot be contaminated to such a degree that there is no danger of radioactive contamination of the operating personnel or workers which are employed for undertaking the repair or servicing work, such repair and servicing operations are associated with an extremely great amount of work, material costs and time, apart from the economic consequences resulting from longer standstill or downtimes of the plant or installation.
Furthermore, it is to be considered that with the heretofore known pump apparatuses which were employed in such fields of application and of the previously mentioned type, the pump, the associated suction device with suction lines, pressure lines and the ejectors for the initiation of the liquid conveyance, and also the pressure container, were each arranged adjacent one another upon a base plate. This, in turn, required undertaking particular safety measures, for instance to prevent liquid leakage or loss at the mountings of fittings, flanges, pipelines and the like.